Drum type washing machine



May 24, 1960 H. CZAIKA, JUN.

DRUM TYPE WASHING MACHINE 2 Sheets-Sheet 1 Filed Dec. 23, 1957 FIG.3.

FIG.4.

INVENTOR Hugo Czaika, Jr.

ATTORNEY May 24, 1960 H. CZAIKA, JUN. 2,937,516

DRUM TYPE WASHING MACHINE Filed Dec. 23, 1957 2 Sheets -Sheet 2 INVENTOR Hugo Czoiko, Jl:

ATTORNEY DRUM TYPE WASHING MACHINE Hugo Czaika, Jun., 3/ 13 Alliiertenstrasse, Vienna II, Austria Filed Dec. 23, 1957, Ser. No. 704,729

12 Claims. (CI. 68-58) The present invention relates to a laundry machine and more in particular relates to a laundry machine having a washing drum serving to contain the materials to be washed, this washing drum being supported for rotation within an outer drum from which outer drum the washing fluid passes into the said washing drum, which latter washing drum has means associated therewith whereby limited quantities of the washing fluid are periodically Withdrawn from the said outer drum, the washing drum also having means associated therewith whereby approximately equal quantities of the washing fluid are periodically withdrawn from the said washing drum.

In prior art washing machines of this general type, provision has, for example, been made for the washing drum to be supplied with the washing fluid through perforate portions of its walls, the washing fluid for this purpose beingwithdrawn from the outer drum. In washing machines of this prior art type, it has been possible to effect a change of washing fluid only by draining and refilling the outer drum at suitable intervals through the medium of suitable valve means which-where desired-have been arranged to be operated by automatic control means.

In recent years, there have been suggested drum-type washing machines having a washing drum including means whereby limited quantities of washing fluid are periodically withdrawn from the outer drum and also including means whereby washing fluid is periodically withdrawn from the washing drum. In one washing machine of this type, the washing drum proper is partitioned in such a manner as to provide it with a lateral container into which the washing fluid withdrawn from the washing drum is introduced in a peripheral direction. The fluid is withdrawn through a hollow axle after having passed this lateral container. However, this construction suffers from the drawback that the provision of the said lateral container results in an undesirable reduction in the capacity of the washing drum and hence the washing machine. Moreover, the construction of this known Washing machine is expensive from a manufacturing point of view. In still another known type of washing machine, the withdrawal of the washing fluid is effected directly within the wash handling compartments of the washing drum by means of scoops arranged on the axis of the drum, the said scoops being connected with each compartment of the inner drum by suitable holes and also being connected to a centrally disposed tubular conduit serving to remove the washing fluid thus withdrawn from the inner drum. The drawback inherent in this known type of washing machine is to be seen in the fact that a sufficiently high rate of washing fluid inflow into the said scoops is ensured only if a positive pressure prevails in the outer drum, this being necessary because the materials to be laundered will tend to obtu- 'rate the perforated area provided for the washing fluid to be'transferred from the outer drum into the wash- :ing drum. 'It will be understood that also in this type :Ofwashing machine the'capacity of the washingdrum is 2,937,516 C Pa tented May 24, 19 60 reduced by the presence of the scoops therein. Moreover, scoops of the type 'just mentioned can only be used in drums having horizontally extending partitions.

According to the invention, the he'reinbefore indicated drawbacks of known washing machines are eliminated in adrum type washing machine having a drum receiving the materials to be washed, which drum is supported for rotation within a shell or'outer drum from which latter the washing fluid can be transferred into the inner or washing drum, and in wlich the washing drum is provided with means whereby limited quantities of washing fluid are periodically withdrawn from the outer drum, and in, which further means are provided whereby approximately equal quantities of washing fluid are periodically withdrawn from the inner washing drum, so that the washing fluid is constantly circulated through the washing drum, by providing, according to the invention, on the outside of the washing drum at least one scooping duct which extends from a peripherally directed opening along the base of the outer drum or shell and substantially radially towards an inlet opening of the washing drum, which opening is disposed in the vicinity of drum axis, and by providing, also according to the invention, on the outside of the washing drum at least one drainage duct which extends from an opening in the drum through part of its length in a substantially radial directiontowards a discharge opening disposed in the vicinity of the drum axis. Thus, in view of the fact that the said scooping and drainage ducts are disposed on the outside of the washing drum, the wash handling space within the washing drum is no longer restricted in any way. This arrangement according to the invention affords still another advantage in that the said scooping duct will even be capable of performing a fluid scooping action in cases in which the liquid level in the outer drum'is very low. Moreover, by selecting a suitable design of the scooping ducts it is possible for maximum utilization of the scooping chamber to be provided for. It will also be appreciated that the action of the scooping duct or ducts can no longer be interfered with by the material to be laundered. Therefore, even with no positive pressure prevailing in the outer drum, the drum-type washing machine of the invention will always operate in a highly satisfactory manner. The arrangement of the invention ensures that the quantity of washing fluid withdrawn from the washing drum will always be the same as the quantity of washing fluid recirculated into the washing drum. Thus, the invention provides for a particularly advantageous solution to the problem of continuously changing the Washing fluid contained in the washing drum in a completely auto matic manner and without the use of change-over valves and the like, the invention making it possible'to effect a gradual transition from cold water to boiling suds and back to cold rinsing water. v 1

The aforestated problem is solved to a high degree of perfection, also according to the invention, by providing the outer drum or shell with 'means permitting washing fluid to be introduced at a controllable rate in the form of a continuous flow. These means are conveniently incorporated in an overflow-type metering device comprising one water chamber and one discharge chamber, which chambers are separated by a slotted partition. This arrangement permits the flow of washing fluid to the machine to be metered in a satisfactory manner.

The invention may be performed in various different ways but one particular embodiment will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a central vertical sectional elevation of 'a drum-type washing machine according to the invention;

Fig. 2 is a transverse sectional view taken along th line 2-2 of Fig. 1;

Fig. 3 is a plan view of the washing machine in which the outer drum has been cut away to show further details;

Fig. 4 is a transverse sectional view taken along the line 4-4 of Fig. 1;

Fig. shows the washing machine in a front elevational view, including the flow metering device;

Fig. 6 is a front view, on a large scale, of the metering device; and

Fig. 7 represents a longitudinal vertical section of the:

metering device taken on line 7-7 of Fig; 6.

Referring now more in particular to the drawings, Fig. 1 shows the frame 1 of the washing machine which supports a bearing 2 in which the drum 3 intended to receive the materials to be washed is carried for rotation. The drum 3 is adapted to rotate within a stationary outer drum or shell 4 from the sides of which there extend vertical walls 5 which form part of the frame structure of the machine. Provided in the front face of the drum 3 is an aperture 6, and the outer drum 4 also has an aperture 6' formed therein, the latter aperture being closed by a cover 7 hinged at 7a; the two apertures 6 and 6' permit the materials to be washed to be introduced into the inner drum. A supply line (not shown) serves to introduce into the outer drum a supply of washing fluid which is sufficient to fill the drum up to a level 5' the height of which above the bottom of the drum corresponds to between approximately one-sixth and one-fourth of the diameter of the outer drum. Provided at the bottom of the outer drum is a drain pipe 8 which is controlled by a valve 9. The washing machine further includes a pipe 10 permitting steam to be introduced for the purpose of heating the washing fluid.

In the following paragraphs there will be described the means provided on the washing drum 3 for the purpose of periodically withdrawing a certain quantity of washing fluid from the outer drum and for periodically discharging an approximately equal quantity of washing fluid from the inner drum.

The o'utside of the peripheral wall 11 of the inner drum 3 has attached thereto by soldering, brazing or welding sheet-metal channels of U-shaped cross-section in such a manner as to provide shallow rectangular ducts 12, 12' (Fig. 3) which respectively extend from circumferentially directed openings 13, 13', first following a substantially helical path over the periphery of the drum, then formingan anglearound the base corner 14 of the drum and finally extending in a substantially radial direction with portions 15, 15' to an aperture 16 in the rear wall of the drum 3, the aperture 16 being covered with a piece of perforated sheet metal. Where the two rectangular ducts 12, 12 meet they are separated by a partition 17. Upon the drum being rotated in one direction, or in the other direction, part of the washing fluid contained in the outer drum will flow into the respective opening 13 or 13', entering the associated duct 12 or 12, and, upon the respective duct being raised due to the rotation of the drum, the fluid will pass the duct in the direction of the arrow in Fig. 3 so that the fluid flows through the bend 14 and enters into the respective duct section 15 or 15' from which point the fluid will finally flow into the interior of the drum through the perforated member 16.

In a similar manner approximately the same quantity of Washing fluid will be withdrawn from the inner drum during each revolution thereof, this action being repeated periodically in a manner similar to the action of withdrawing fluid from the outer drum for introduction into the inner drum. For this purpose there is provided near the front end of the periphery of the inner drum a discharge opening 18 which is covered with a piece of perforated sheet metal, this opening leading to two ducts 19, 19 formed by sheebmetal channels extending symmetrically along helical lines about the periphery of the drum, then extending around the corner 14 of the drum and finally comprising substantially radial portio'ns 20, 20

which extend towards the axis of the drum where they debouch into a discharge chamber 21. This discharge chamber 21 has the shape of a stationary pot-like member which is secured to the outer drum, the pot surrounding the bearing 2 with which it is concentrically arranged; the inner wall of the discharge chamber 21 is formed by a disc member 22 which has two openings 23, 23' formed therein, the ducts 20, 20 being respectively co'nnected to the said openings. Connected to the bottom of the chamber 21 is a drain pipe 24.

Thus every revolution of the washing drum 3 in either direction will cause the perforated member 18 to be submerged in the pool of Washing fluid contained in the outer drum and will further cause a certain quantity of washing fluid to be introduced into either the duct 19 or the duct 19', this fluid then flo'wing through the respective duct 20 or 20' into the discharge chamber 21 from which it is drained through the pipe 24.

It will be appreciated from the foregoing description that during each revolution of the inner drum 3, independently of the direction of rotation, a predetermined quantity of washing fluid will be withdrawn from the outer drum 4 to be introduced into the inner drum, and that also a predetermined quantity of washing fluid is withdrawn from the inner drum to be introduced into the discharge chamber. By dimensioning the inlet opening 16 and the discharge opening 18 as well as the ducts 12, 12' and 19, 19, in a suitable manner it is easy to provide for the quantity of washing fluid discharged during each revolution of the drum to be approximately equal to the quantity of fluid introduced thereinto, the result being that the quantity of fluid present in the washing drum will be maintained substantially constant except for such variations as may be caused by the varying amounts of material to be laundered and the varying ability of the material to absorb the fluid.

The washing machine of the invention is preferably operated in the manner described below.

The materials to be washed are introduced into the washing drum through its front aperture 6; then cold water is introduced into the outer drum in a suflicient quantity for the scooping apertures 13 to be capable of scooping up a predetermined quantity of water whenever they pass through the pool of liquid. Experience has shown that the maximum rate of fluid flow required for an eflicient wetting and rinsing action is approximately 1 litre per minute per kilogram of material to be laundered. Now steam is introduced into the machine through the pipe 10 until the water has attained a temperature of approximately 40" C. (104 F.); at this point a suitable washing agent is added to the water and the introduction of steam is continued to cause the washing fluid to come to a boil, the washing action using the boiling fluid being continued for a suitable period of time. Following this, cold rinsing water is introduced into the outer drum, a suitable rinsing agent being added; during this part of the washing cycle, the washing fluid will be cooled gradually until it assumes the temperature of the inflowing cold water, while the laundry is being rinsed.

It will be appreciated from the foregoing that the washing machine of the present invention permits of being operated while water is continuously being introduced and discharged in such a manner that the wash is constantly brought in contact with fresh washing water and that there is eflected a gradual transition from hot suds to cold rinsing water. The inner drum of the machine may be rotated either continuously in the same direction or it may be rotated alternatingly in both directions, the manner of operating the drum not affecting the mode of operation of the machine. It is further possible without any difliculty to provide for a fully automatic washing machine by providing the machine of the invention with suitable means providing for automatic control of the period during which water is introduced, of the rate of flow of the washing water, of the introduction of steam for heating purposes and of the addition of the washing agent.

Figs. 5, 6 and 7 illustrate a device enabling the rate at which water is continuously introduced into the washing machine to be suitably controlled. The device comprises a housing 25 which is divided by a partition wall 26 into a water inlet chamber 27 and an outlet chamber 28, this wall being formed with a slot 26a through which water can flow from the inlet to the outlet chamber. The inlet chamber 27 is in communication with a supply conduit 29 while the outlet chamber 28 is in communication with an outlet conduit 30. The front end of the inlet chamber is closed 01f by a glass closure member 32 which is fluid-tightly secured to the housing 25 through the intermediary of a seal 31. Thanks to the transparency of the closure member 32, graduations 26b carriedby the wall 26 can be seen from the front of the washing machine. The necessary water supply is controlled by a conventional valve (not shown), and water entering the measuring device by way of the chamber 27 will overflow through the slot 26a into the outlet chamber 28 and from there through the conduit 30 and into the outer drum 4. In this way, the quantity of water supplied to the machine is independent of the water supply pressure. The necessary measuring accuracy can be attained by selecting the angles of convergence of the edges of the slot in a suitable manner.

In the drum-type washing machine of the invention the action of raising the suds scooped up in the manner described and imparting potential energy to it results in the laundry to be elfectively sprayed with washing fluid. By comparison it may be stated that no such spraying action is obtained in the first known type of washing machine referred to earlier in this specification, the water being at best flowed gently on the wash in the said machine. Moreover, the said known washing machine has a drawback in that it comprises six webs or ribs, namely, three for the introduction and three for the removal of washing fluid. However, many years of experience have shown that there exists a direct relation between the number and shape of the ribs on the one hand and the efficiency of the Washing action on the other. Practical experience has led to the conclusion that three ribs is the optimum number and that any additional ribs will detract from the efiiciency of the washing machine.

6 cent to said opening; an outlet opening in said jacket; at least one discharge duct on said jacketcommunicating I with and extending from said jacket opening substantially in axial direction with respect to said drum; and a discharge chamber formed in said housing close to said axis of rotation, said discharge duct terminating in said chamher.

2. A washing machine as defined in claim 1, wherein said inlet opening and said outlet opening are each covered with a perforated member.

3. A washing machine as defined in claim 1, wherein the said ducts are made of sheet-metal and have rectangular cross-sections of .low height with respect to their width.

4. A washing machine as defined in claim 1, wherein two scooping ducts and two discharge ducts are provided, which ducts are disposed symmetrically in relation to a line on the periphery of the drum extending parallel to the axis of the drum.

7 opening, and said two discharge ducts are in communi- Moreover, the ribs provided as scooping means in the said known washing machine have a cross-section of very great width so that they reduce the capacity of the drum to a considerable extent.

It will be understood that modifications and variations may be effected without departing from the spirit and scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of .the appended claims.

What I claim is:

1. A washing machine of the drum type, comprising a housing; a drum rotatably mounted in said housing; at least one scooping duct mounted on the jacket of said drum and having a circumferentially directed open end, said duct extending from said open end substantially in axial direction first along said jacket and then substantially in radial direction along the rear wall of said drum; an inlet opening on said rear wall of said drum close to the axis of rotation thereof, said duct terminating adjacation with said outlet opening of said jacket.

6. A washing machine as defined in claim 1, wherein said scooping duct extends along a helical line on said jacket and across the rear wall edge of said drum.

7. A washing machine as defined in claim 1, wherein said discharge duct extends from said outlet opening along a helical line on said jacket and continues across the rear wall edge of said drum.

8. A washing machine as defined in claim 1, wherein said drum is mounted on a bearing, wherein said discharge chamber is formed by said bearing and a stationary sleeve surrounding the same, and wherein said discharge duct debouches into said discharge chamber.

9. A washing machine as defined in claim 1, wherein said housing is provided with means adapted to control the rate at which washing fluid is continuously introduced into the machine, and wherein means areprovided to introduce hot steam into the washing fluid.

10. A washing machine as defined in claim 9, wherein said means adapted to control the rate at which washing fluid is continuously introduced comprises an overflow type measuring device including a water chamber and a discharge chamber, said latter chambers being separated by a wall having a slot formed therein.

11. A washing machine as defined in claim 10, wherein the angle of convergence of the edges of the said slot varies so as toprovide the desired measuring accuracy.

12. A washing machine as defined in claim 1 wherein said washing drum is formed with a materials charging opening through which material to be washed is introduced, wherein said inlet opening is provided in the rear,

wall of said washing drum at a location remote from said charging opening, and wherein said outlet opening is located close to said charging opening.

References Cited in the file of this patent UNITED STATES PATENTS 

